The Twitter service this new UI presents is about a whole lot more — mass-market spoonfed “trending topics” and sponsored content. It’s trying to make Twitter work for people who don’t see the appeal of what Twitter was supposed to be. It all makes sense if you think of the label under the “#” tab as reading “Dickbar” instead of “Discover”.

Like I said yesterday, Twitter no longer wants to be seen as a tool or service — it’s not a backbone to be built a top of. Twitter is a place on the Internet. Twitter wants to be an environment that people spend time at, not a service that people spend time using without every “seeing” it.

I think Gruber is only partially right here. There’s a lot more going on than just setting the app up for monetizing the service. I would guess that any new Twitter user that loaded up Twitter 4.0 verses Tweetie 1.0 will find 4.0 far more comfortable and useable. I don’t think that is the case because they “don’t see the appeal” of Twitter — I think that is the case because Twitter has evolved beyond what it was when people like Gruber and I first started using it.

One thing that Gruber points out that is really at the heart of the matter is the waining support for 3rd party Twitter apps. I really wouldn’t be surprised that come 8 months from now all 3rd party apps are severely crippled in someway compared to the official Twitter clients — so much so that it becomes masochistic to use them.

A lot of people are surprised that I still use the official Twitter apps — the reason I do is because I know that they are the only ones that will be around in the future. That is: I don’t think Twitter likes that there are 3rd party apps and because of that I think they are slowly trying to kill them off. Example number one was the integration in iOS. Example two is the killing of photo sharing services with the pic.twitter.com service.

It’s a matter of when, not if, Twitter is going to kill 3rd party clients.